From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F34EDC5DF60 for ; Tue, 5 Nov 2019 23:57:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96C82222C1 for ; Tue, 5 Nov 2019 23:57:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LANLIsSL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730624AbfKEX4Y (ORCPT ); Tue, 5 Nov 2019 18:56:24 -0500 Received: from mail-vk1-f202.google.com ([209.85.221.202]:44629 "EHLO mail-vk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730543AbfKEX4W (ORCPT ); Tue, 5 Nov 2019 18:56:22 -0500 Received: by mail-vk1-f202.google.com with SMTP id 131so1158607vkb.11 for ; Tue, 05 Nov 2019 15:56:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=OH2SjYe0B8esWxTAcCgR+62MsPomBC+RzRSTMU1rFk8=; b=LANLIsSLRt+jERn9z/YC1fWtMQVX8zCypiEu6yw+A7ph5wykxHwT9wsDMQDlDMl2rg stArYiAU/nb/XpN8wDOhlGyfTc0fdCPVyLoqsctOyYeGq24aghzkvptD+XVbn9Xq4Qx2 yxJPdKckjUE2Le0UST7HQhi45E/yHrtn4L5mNNxo+7JL+AcIOJugxBvuaOWMfQaRKd19 pgc7iEsvYu0XarG32KP1cibZw6Yh6odpoBcAbe/UiVxBTEh1uk9MrGBjI2ktk5L02xPX x9VA45PGyhIT4mZVHxYbG80ZMkQKYGWocfpS2nmfUWNgOvxc1mQu8MLaMnzS4vac3Qt1 JBZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=OH2SjYe0B8esWxTAcCgR+62MsPomBC+RzRSTMU1rFk8=; b=TUyR+rqVaJspadU916/klyNUk0i8ONOlGv9SZsAV5s9HKza5n91keL9FcWiuFSWWxv Gd4eQABF9uuQ/3Rk6czEkkHKKfoaTH4LNdbLDBEjo/R/BQb8MTT9Ug+8NFPBEycuIPJB eKS3VR32pexg0JOVTPP596UhE6+UM9VmasM9pwTXNAEdwWEssQ7ISPhEMTg12n/4IDdY 2mlEMVFqDhKRxIilPSFphCLY/pC/7OunV3HRiJCYBK04oH5fEO9JhPOLr+YCBZWaQb6Q 6hUR5LzanT4jWQIMYe3sSN3tbLFubi5/R02RrAtx/RucGrPaEPF+AK0mf/cHro90BdcG DUsg== X-Gm-Message-State: APjAAAVu8JcdFwcSSsU3brkkElPcmjrZfHzh0AzJqeVOR0gjxeEH7/nP oj4l8DvJp/gAZfYWR92SvsGmryi2H1I4U/diwME= X-Google-Smtp-Source: APXvYqxFzno9MSXI4Ly95n1ixFuKJLy5PBpFiCEvi59EZLe1JMvD55HUp/RJhtm2+ZnxbDY2T+pgxUE1vx1ZzWw2zK4= X-Received: by 2002:a67:ef0c:: with SMTP id j12mr9381038vsr.201.1572998180740; Tue, 05 Nov 2019 15:56:20 -0800 (PST) Date: Tue, 5 Nov 2019 15:55:56 -0800 In-Reply-To: <20191105235608.107702-1-samitolvanen@google.com> Message-Id: <20191105235608.107702-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191105235608.107702-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog Subject: [PATCH v5 02/14] arm64/lib: copy_page: avoid x18 register in assembler code From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel Register x18 will no longer be used as a caller save register in the future, so stop using it in the copy_page() code. Link: https://patchwork.kernel.org/patch/9836869/ Signed-off-by: Ard Biesheuvel [Sami: changed the offset and bias to be explicit] Signed-off-by: Sami Tolvanen Reviewed-by: Mark Rutland --- arch/arm64/lib/copy_page.S | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/arch/arm64/lib/copy_page.S b/arch/arm64/lib/copy_page.S index bbb8562396af..290dd3c5266c 100644 --- a/arch/arm64/lib/copy_page.S +++ b/arch/arm64/lib/copy_page.S @@ -34,45 +34,45 @@ alternative_else_nop_endif ldp x14, x15, [x1, #96] ldp x16, x17, [x1, #112] - mov x18, #(PAGE_SIZE - 128) + add x0, x0, #256 add x1, x1, #128 1: - subs x18, x18, #128 + tst x0, #(PAGE_SIZE - 1) alternative_if ARM64_HAS_NO_HW_PREFETCH prfm pldl1strm, [x1, #384] alternative_else_nop_endif - stnp x2, x3, [x0] + stnp x2, x3, [x0, #-256] ldp x2, x3, [x1] - stnp x4, x5, [x0, #16] + stnp x4, x5, [x0, #16 - 256] ldp x4, x5, [x1, #16] - stnp x6, x7, [x0, #32] + stnp x6, x7, [x0, #32 - 256] ldp x6, x7, [x1, #32] - stnp x8, x9, [x0, #48] + stnp x8, x9, [x0, #48 - 256] ldp x8, x9, [x1, #48] - stnp x10, x11, [x0, #64] + stnp x10, x11, [x0, #64 - 256] ldp x10, x11, [x1, #64] - stnp x12, x13, [x0, #80] + stnp x12, x13, [x0, #80 - 256] ldp x12, x13, [x1, #80] - stnp x14, x15, [x0, #96] + stnp x14, x15, [x0, #96 - 256] ldp x14, x15, [x1, #96] - stnp x16, x17, [x0, #112] + stnp x16, x17, [x0, #112 - 256] ldp x16, x17, [x1, #112] add x0, x0, #128 add x1, x1, #128 - b.gt 1b + b.ne 1b - stnp x2, x3, [x0] - stnp x4, x5, [x0, #16] - stnp x6, x7, [x0, #32] - stnp x8, x9, [x0, #48] - stnp x10, x11, [x0, #64] - stnp x12, x13, [x0, #80] - stnp x14, x15, [x0, #96] - stnp x16, x17, [x0, #112] + stnp x2, x3, [x0, #-256] + stnp x4, x5, [x0, #16 - 256] + stnp x6, x7, [x0, #32 - 256] + stnp x8, x9, [x0, #48 - 256] + stnp x10, x11, [x0, #64 - 256] + stnp x12, x13, [x0, #80 - 256] + stnp x14, x15, [x0, #96 - 256] + stnp x16, x17, [x0, #112 - 256] ret ENDPROC(copy_page) -- 2.24.0.rc1.363.gb1bccd3e3d-goog